Unfortunately, when you cut a parent out of your life, it is very hard to maintain contact with your siblings. The siblings have to pick sides and will often pick their parents side. Even if they don't mean to. Even if they don't take sides and just remain as neutral as possible, they will find it hard to not mention them. (Talking things they've been doing with them/the times they have seen them.)
When they do mention them it will sting the person who has cut off their parent(s.) It's so hard to keep a relationship going with close family when you go NC with one or more of them. (And it's particularly hard if it's a parent you have cut off, to remain in touch with your siblings.) In many cases you have to make a choice. Try and heal the rift, or give them all a wide berth. It's simply too hard/too painful for many people to keep seeing siblings when the siblings have their parents in their life, and they don't.
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