New relationship after death of partner

My boyfriend who is also the father of my now 5 year old daughter passed away in 2019. We were together for almost 5 years when he passed and my daughter was 3 at the time. Needless to say it was the hardest thing I’ve ever been through and I still think about him every day.

However it’s been 16 months since his passing, and I started seeing someone about 3 months ago. First it was just casual but now it’s getting pretty serious. He had already met my daughter way before anything happened between us. He was my brother in laws best friend so he’s been in my life for years. He’s so kind, funny, respectful, and is great with my daughter. He hasn’t been introduced to her as my boyfriend or anything, he’s just kept coming around as he usually had so hes very close with my family already.

Anyway I’m worried on how to best “announce” our relationship . Not just to my family and daughter, but also to my late boyfriends family. I know my family will be supportive no matter what but I am worried as to what my exes family will say. If they’ll think it’s too soon or if they’ll be offended that I am moving on. I asked my best friend and she said I don’t have to tell my exes family anything but I do think I should at least tell his parents and sister as they were really close to him. I just don’t know what’s the proper etiquette here. Thoughts? Suggestions?