jealous?

So we all know are hormones are a little off with a new baby. I'm not sure if anyone can relate but I feel extra jealous about things lately. The biggest one is that my in-laws watched our 3.5 month old son the other night for a few hours and when we got him they went on and on about how they got him to giggle (for the first time). I just felt so sad and mad and jealous. Like I was robbed of that moment. He's done little ones before, but then tonight we visited them and they got him to do it again and I felt the same way again 😕I tried to act like oh yeah I've heard it before it's cute- but I'm a horrible liar and I think they could tell. Then there's other stupid stuff like they buy my SIL (their daughter) a bunch of stuff for her baby that'll be born any day and I just feel jealous about it. I hate feeling this way...