Baby shunned from SO's family

My SO and I have been together these years and have a one and a half year old daughter. His family is very abusive toward my SO since he was younger (he's the only guy) and there was severe favoritism which has caused him to be estranged from his siblings. We were in contact and seeing his family all the time when our daughter was born and nobody has ever bought her a present. His Dad even gets her name wrong. His sisters call her "that baby" even though they all older than twenty. They call her a sin because we aren't married. His cousins and aunts and uncles don't even acknowledge her, if they come over they don't even look at her because she's a "sin" and a "disrespect to god". His Dad tried to strangle my SO a few months ago. His sisters don't do anything, they don't have jobs - they just mooch . His sister found out she was pregnant (her and the guy aren't married either, not to mention he treats her badly and they live with his parents with 4 children from his ex and there's a lot of drug use) but everyone in his family is thrilled for them and throwing them this huge baby shower (we aren't invited, and we never had a shower because his family said they wouldn't buy anything or come at all), they're all talking about it and acting like it'll be the first baby in the family even though our daughter has been here the whole time and has been ignored and shunned by his family... advice??? I know I sound petty and shouldn't let it get to me, but I can't help it 😔