Well, I can't name any because they aren't there to name. Being a parent offers us so many more excuses than the non-parent. We have little mouths to feed, errands to run, kids to taxi, food to clean off the carpet, etc, etc . . . It becomes so much easier for us to make that extra excuse to not sit down and write that story we wanted to write or work on our novel. We have lunches that have to be made first.
Baths come next.
Finally, well, we are just too tired. Okay - we get tired and we must sleep. That's a given. We watched T.V. instead. There are legitimate times that you really can't write, but there are many more times you could have.