So you decided to have kids. You’ll have some days that you won’t be at work.
So you decided to go part-time. You’ll miss out on some stuff.
You took this job to make money, but you’re really an artist. Grow up and do the job to the best of your ability. Or find something requiring less attention and less of your focus so you can concentrate on your art. But don’t make us indulge you.
Accept the consequences for your actions and deal with it.