I too am a doula with a child. Luckily both my partner and I work a flexible schedule. However, my dh goes out of town alot, so I often have to at least line up a backup friend who is willing to come over in the middle of the night if need be. I find that a single, childless friend works for this, because they can often come over in the middle of the night, without me having to drop my child off because they are not leaving a child behind. This would be great with family, like your mother.
I don't take alot of clients yet, about one a month and I find that helps alot. My clients usually know mid-day that they are at least starting to have labor come on and I usually have a couple of hours to "get my act together". And so far,
, it has worked out beautifully every time.
My advice is just prep your clients in advance to let them know you need time to figure out your childcare and then have a few different options in mind. Also, just in case, have a backup doula. If nothing else, she can go for you if you are in a real jam.
Good luck ladies!!!
Also, I am on a great doula list. It is very informative and nationwide.... If you are interested email me privately, as I have to invite you to the list. And check yahoo groups, it has a few good ones too.