I have no advice as I am 3 months behind you. Ds1 was an absolute dream with his sleeping right through and regular daytime nap routine. Ds2 is a complete law unto himself. He does sleep in the day, but nothing you can particularly rely on. He just does everything so much more than ds1.
So ds1 never had any separation anxiety, if I walk out of the room ds2's world falls apart.
People used to try to get a smile out of ds1, whereas ds2 is a little tart, smiling and chuckling at everyone.
Ds1 worked and worked on sitting up, crawling, walking over a long period of time. Ds2 does everything and goes everywhere constantly.
If you told ds1 "no" he would stop, and not touch the item again. Ds2 sometimes stops, in order to get the praise (and he claps himself). He then goes straight back to whatever he was touching.
Trips to A&E with ds1: 0 in 3 years.
Trips to A&E with ds2: 1 in 8 months.
Ds1 current favourite activity: doing jigsaws and playing boardgames
Ds2 current favourite activity: crawling/ climbing everywhere and chewing jigsaw pieces/ nicking parts of games
And I think it is wonderful that they have such different personalities, but utterly utterly exhausting.