Hancock's has Butterick on sale for $1.99 right now. I don't know a specific pattern but all the pattern companies have simple pj patterns, the main difference is who is on sale.

Look for a one piece pant pattern and I think a pull-over style with raglan sleeves are the simplest to sew for a top. The pattern doesn't have to be for pjs either, it is just pants and a top, you know?

I've been in jammie mode this weekend, using several different patterns. On just about all of them, I've had to cut some off the top at the waist to reduce the rise, even over diapered bottoms. I've also added length to the bottom hem. So you might want to double check those measurements against some of your daughter's current pjs.
HTH and good luck!