Opening up to my mom...when is the right time?

I opened up to my dad a few years ago. I’m glad he still loves me because I’m his son. He’s still trying to understand me, but I’m glad he’s putting in some effort to. Yesterday we talked about it again and he told me “attraction is one thing - now, I’m not trying to offend you or anything, this is just my belief - that marriage is between a man and a woman. If you feel that way, I can’t do anything about it. I just want you to be happy, financially secure, and successful. Make sure you finish school first though.” When he told me that I was glad he was being a bit more open-minded because he didn’t want to offend me. I felt it was more of an “agreed to disagree” sort of thing because he’s my dad and I’m his son. He still loves me no matter what. Even after, we still get along as if it didn’t happen. We talk about life and still have happy moments and jokes. It’s funny he said to finish school first though, but it shows that education is super important to him and he just wants to see his kid be happy and all that. However, I haven’t opened up to my mom yet. Reason being is that she’s grown up more traditional than my dad. She moved from the Philippines to the US when she was 18 and also grew up Catholic. She’s not one to really open up and express her thoughts and emotions (very unhealthy). Additionally, she’s in remission and still a bit in disbelief that she had cancer. When is the right time to tell my mom I’m gay? I was planning to tell her this week because I was super inspired by “Love, Simon”. She may still be dealing with when my brother opened up to being queer a few weeks ago and I don’t want to give her another thing to worry about...