How to stay sane with a 1 and 3 year old?

Sounds like you need a planned activity in the afternoon too. Some painting, gardening (if you have a garden), water play (potentially in the bath), cooking, or maybe just go for a walk outside (scooter for the 3 year old?)

I wouldn't expect them to be able to play together at this age - not for more than 5 mins at least

There is no answer, it's just a phase, but a terrible one. The baby will trash the older child's games, there'll be tears, it's hell. Get out into the garden or back to the park, then at about 4pm they should be knackered enough to have some Peppa Pig in a subdued state whilst you cook or whatever.

Our children spend a lot more time in bed than yours do. We have a similar routine, out in the morning, come home for lunch. But then they both go down for a nap at 1pm. 14m DD wakes between 2 and 2.30 because she naps in the morning too (9-10am), 3yo DS wakes between 2.30 and 3 but sometimes sleeps later.

Then we start the dinner-bath-bed routine at 4.30pm. 14m DD lights out at 6pm, 3yo gets extra stories and chats and lights out 6.30-7pm.

Sometimes I feel like mine barely get any day, they spend so long eating and sleeping!

Ours can only play with "baby toys" together, which means the train set hasn't had much use for six months. Oh well, such is life. 3yo would love to play with his sister but she just ignores him!

I highly recommend buying a visual timer (hourglass or TimeTimer where the red circle vanishes) and starting Quiet Time with your 3yo where he plays in his room by himself. I understand that you sort of attempt this and he just calls out to you, but I think it would be a huge boon to you so I'd try to ride the hump out. I'd put any toys the little one ruins into 3yo's room so he's dying to get in there and play with them uninterrupted and keep uncontroversial toys in communal play area.

Also, my friend swears by a playpen. Sometimes the little one is in it, but often it's the bigger one who wants the wall around what he's doing!

A walk might be a good plan... can they both go in buggy? Or scooter for 3 year old. I used to have the most ridiculous “reasons” for walks when mine were that age.... eg walking to the “further away” letter box to post a letter, going to supermarket for one or two items, etc. I used to go pretty much all weathers just to stay sane.
I’m pretty sure they had a bit of tv time after that, so I could (recover) have a cup of tea!
Maybe have a friend with kids round (if you’re able to) - put the kids in the backyard it’s always easier if you’ve got someone to chat to.
I suppose I’m saying have a planned activity but it doesn’t have to be a mega plan just something to keep you all occupied for a little while.

I tell DS if he's playing with anything he doesn't want his sister to mess with he has to do it on the dining room table and he's usually quite happy to do that. I find the afternoons drag longer than the mornings so we stay home until after lunch. DD usually naps between 10-12.

I had 3 under 3...
Much easier than 12, 14 +15!!
Bedtime routines make the days easier... Bath most nights - lots of toys and bubbles. Bath seat enables free hands for drying up!
Double check bedroom for hazards if your dc will be playing unsupervised..
Once my 7yo managed to climb out of a velux window - to get a ball he knew was in a gutter . Who would have guessed it would cross his mind? Def not me!!

My two are almost exactly the same age as yours and we have a similar routine during the day. I struggle with the afternoons too, I am running out of steam by that stage and desperate for DH to come home at 5pm to give me a 20min break (My youngest is a terrible sleeper so I've often been up since 5am ). I'm really looking forward to the library opening on Mon. That was a big hit previously for me. My eldest will happily look through books themselves and the youngest will just enjoy toddling about or having a story. Kills a good hr or more with the walk there and back.

I had a baby and a child of 2.10 months and I remember this time of life - it felt like every day was so exhausting as the kids both got up so early! For me I used to work on tiring out the older one at the park or going to groups/classes. They didn’t really nap at that age so when the baby was down I would be playing with them.
Honestly I would not have survived without a couple of hours of CBeebies a day in which I had a coffee or read a magazine. I was too exhausted to master housework until the weekends.

No advice I'm afraid, but I can commiserate, I have 18 month old and nearly 4 year old. Thankfully my youngest has a two hour nap in the afternoon, so I try and keep them both out all morning, then lunch and nap. After nap and before tea is a killer. Lots of TV, or as others have said, take them for a walk to the postbox or something just to kill a bit of time. Playgroups allowed to open next week in the UK! 🎉🎉🎉

In all honesty, I think it’ll get easier when the youngest is a bit bigger and you have to just get through it. I found it really hard at that age but my 2 and 4yo are now quite kind to each other and will play together nicely in the garden. A year ago they would wind each other up, the little one would try and do something dangerous or destroy the eldest’s drawings or generally be a pain.

I also have a policy that it's DSs job to keep "his" games/projects out of his little sister's hands. At the moment that is heavily facilitated by me (I will direct him to do certain activities in certain sensible places she can't get to) but I expect him to take more ownership of it as he gets older.

Also, I have a friend with boys who are nearly 5 and just 3 (so same age gap but her youngest is the age of my oldest). Talking to her and getting hope is sometimes what gets me through! She says they play together all the time. Not without tears, but they really are playing WITH each other and occupying each other socially

It's easier now they are 5 and 3...

Sorry!

The first 3 years are just survival!

It's much easier now! Mind are just turned 3 and just turned 5.., from lockdown last March I could just about manage a walk with both not actively trying to kill themselves!

I also have a three year old and a one year old, I feel your pain, as lovely as they are.

I find the mornings easier- film in my bed before breakfast, go and make brekkie with the three year old and have the baby watching in high chair, then normally return to bed to watch end of film and get dressed, brush teeth etc.

3yo content playing with his toy cars for an hour or so, with me in the room helping out and keeping 1yo distracted with toys of his own.

Snack around 10.30 and lunch at midday.

I try to go to playground straight after lunch and 1yo will nap on way home and usually stay asleep for a little bit longer when we get in, giving me time for a coffee and a bit of time for 3yo to play without interruption.

3pm ish baby wakes up and both can watch a bit of tele together normally without making each other cry.

4pm ish cook dinner together.

Witching hour after dinner until husband finishes work at 6 where I have NO ideas about how to manage overtired three year old and getting tired one year old. Just break up little fights and stop them hurting each other for an hour and a half, before calm bath books and bed.

Knackering, isn't it? A sloowwww morning is my recommendation though.

Put a baby gate on eldest dc bedroom door and set him up with trains and lego in there. Tell him if he brings them out then he has to let sibling play with them and to expect sibling to trash structures. Then play in the hall with little dc. Roll a ball back and forward, knock down towers, draw with water pens, read books, sing songs, fold laundry, sweep the floors and have the baby dust etc etc

I found messy play or water play were the only things that really worked to entertain them both together at that age. I got a tuff tray and stand and manage the mess by doing it outside

Honestly you're in the eye of the storm right now but it does get better. 2 and 4 is much easier and then it just gets better and better so hang on in there, you're doing great. I always remember the time when mine were 1 and 3 as the most challenging. But then I look back at pictures of that period and they were just soooo cute!

It is not possible to stay sane with two that age, I'm afraid. Just embrace the chaos and know that when they go to school, you will get some if yourself back

There are 22 months between mine. They are 9 and 11 this summer. Those first 5/6 years are a blur. They never played nicely. Still don't. In my experience It's just something you have to get through until they can start school.

Of yourself, I mean

Tonight I was surrounded by screaming 16 month old and 3.5 year old, both screaming for different reasons, both normally wonderful but absolutely exhausting and I thought "my god, is this the peak of the worst? Or does it get even worse? Cause they have taken every atom of my being, there is nothing left for me, and each day just keeps on coming with no respite" and I thought about finding a thread where others had a similar feeling or experience with these ages. Then I saw this thread. Just a strange coincidence. Dear god its hard isn't it

Put the trainset / playdoh etc on the dining table for 3yo to have away from 1yo.