Sil hasn't made contact with us for nearly a year

Sigh, no one reads a caveat these days. See what I mean about the written medium?

I'm reading this more as the two women had a friendship. OP bought her friend (SIL) a present and invited her to come and meet her child. Her friend (SIL) didn't buy her a present in return and didn't come to meet her child.

OP is confused as to why their friendship has changed.

Their relationship is none of my business. I'm just annoyed that she hasn't met our youngest child, and the lack of presents/thank you is really rude.
And yet you don't comment on BiL, who is their actual uncle by blood.
Why are you blaming your SiL for your BiL's lack of interest?

Wondering if I should contact her? But say what exactly?
Why has your husband not contacted his brother, or her?
Why is this up to you?
maybe your DH & DB aren't very close.
Why do you think BiL's wife is responsible for how much contact BiL has with his brother & your DC?

If you want to contact her - do so.
As to what to say - what's the big deal? "Hi, haven't heard from you in so long, how are you both, do you want to arrange to meet".

Conversely, leave it all to your DH & BiL. but either way, stop blaming SiL for BiL's lack of contact.

Agree it makes no sense. If thr bil said thanks, if they see him often, wtf is the op going after his wife like this.

It's not about wifework though surely? It's about relationships.

If I bought someone a present I would hope they would thank me for it. Even if I physically handed it to someone else to pass on it would be nice if they text me themselves.

I work with a friend's sister. If I hand a present for my friend to her sister, should I not expect her to text me to say thanks?

Equally if my MIL buys me a nice gift, I would feel awful not to buy her something in return. My husband would very possibly take charge of choosing something but I'd be checking what he'd got to make sure i thought it was a nice gift too. And if he got something I wasn't sure she'd like I'd possibly add to it. Because, you know, she thought of me so I want to think of her.

I agree with this!

I don't get why it's BIL's job to say thank you for a present for his wife?

If someone sent a present to my DH, it would be him saying thank you- not me.

What a number of posters, myself included, have pointed out, is that the SIL is unlikely to just not be saying thank you out of being a cow. It is highly likely that she has some major things going on and that a thank you text is the least of her worries and that maybe OP should be more worried about the person than the perceived protocol.

They aren't friends though are they? I know when my friends are unhappy and why - and that would inform my response to any perceived rudeness.

So how come you’ve no clue if he’s still married if his wife is ok and his thanks are not enough>

it does feel like you’re looking for some drama op amd want to go for this woman.

have you nothing else to occupy you?

Because as I said, it's all very cloak and dagger and you just don't ask those things.

Well if you're not asking & SiL isn't telling, you no longer have the relationship you once thought you had. You've sent her a text today - if she responds, be friendly, play it by ear. If she does not - consider that she may be having marital troubles & not want to confide in anybody still within BiL's family circle.

That's really good advice @KettrickenSmiled

I don't understand PPs slating OP. She spelt out exactly how she has realised slowly looking back that SIL hasn't been in touch and that particularly bc she hadn't thanked for gift that was unusual and then asked if in these circumstances being told by MIL that there were issues, whether she should contact SIL direct

I don't see the benefit of PPs nitpicking and making assumptions on this thread, rather than giving constructive advice. Other than it's AIBU board which brings out the unhelpful posters from the woodwork.

She could be going through something.

There is also another possibility, which I only bring up based on personal experience. She could also be avoiding her bil and sil (you) on purpose because you've offended or upset her somehow. I would imagine, if she's felt mistreated by her husband's brother and wife, the last thing she wants to do is spend more time with them... new baby or not. And gifting etiquette doesn't really apply when we want someone to bugger off.

My thoughts would be they probably are having marital issues. Perhaps they are living separate lives in the same home. She probably didn’t buy all the Christmas presents this year and BIL has totally forgotten or not bothered. No excuse not to thank you for her gifts. I can see you’ve sent a text, that’s what I’d have done too, happy new year is a great excuse to get in touch with someone. Just let her know you’re available for a coffee / chat etc if she needs it. Sounds like she’s checked out of her relationship but doesn’t mean you can’t be friends still

Maybe she just not that into you....

If she hasnt contacted you in a year maybe just go oh well and move on
Maybe she was just being nice to keep the peace and is done with that now for whatever reason.
She dont owe you a relationship and from her end, if you only text her once, then its safe for her to assume you dont really care to much
Your coming off more like you want the gift and 'omg look at the cute baby'

It’s Very ungrateful that they didn’t say thankyou for presents, I know a lot of people like that. Although it’s not the be all and end all if they didn’t buy your kids gifts? Teach your kids that it’s experiences and spending time with people that matters, not materialistic things.

Can I ask why you have came to strangers for advice instead of just sending a simple message saying “hey i feel you’ve been abit distant lately, is everything okay? We would love for you to meet little man”. There could be a number of reasons their being distant, maybe they’ve split up so she’s no longer your sil? Maybe their struggling with fertility and seeing a baby would be too much?

The cost of living crisis is insane, a lot of people have cut back on spending on gifts this year. I’m sure your kids get plenty of you, materialistic things shouldn’t matter

If you’re so concerned about her like you claim, why not contact her or the bil rather than come to a bunch of strangers on internet?