Would bad ballast cause other lights to flicker?
I am at my Mom's house and she is having a problem with lights on one breaker flickering. The house is about 60 years old and the lights that are flickering include incandescent bulbs and a 2-tube fluorescent fixture. She first noticed the problem a few weeks ago (the hallway and bathroom lights with incandescent bulbs flickered), but we couldn't replicate it. Today, however, she showed me that the fluorescent fixture in her kitchen wouldn't fully light (had spiral flickering along the tubes). We tried changing the bulbs, but the new bulbs also flickered. I looked at the ballast and it looks like it has oil/grease on it so I am assuming it is bad. The question is, would the bad ballast on the fluorescent fixture cause the incandescent bulbs in other fixtures on the same breaker to flicker?
I have contacted another family member on a recommendation for an electrician we can call, but in the meantime I am wondering if anyone has any insight on this.