I currently shoot a 368 gr arrow out of a bowtech equalizer set at 43lbs. My KE is less than 40lbs.
I use a Muzzy 125 gr, 3 blade broadhead.
I shot at four deer this year.
Deer #1, an old doe. Pass thru.
Deer #2, big 3.5 year old doe. Pass thru.
Deer #3, BB. Pass thru.
Deer #4. No pass thru but the arrow hit the far side leg bone. Broadhead did chip the humerus but didn't break it.
I've killed deer and hogs with as little as 32 ft pounds of KE. Shot placement is of course, key. Have her keep her shots to 30 yards and less.
Also,
forget about speed. With low poundage set-ups you'll want her to have a heavy arrow. Momentum is more important for us light poundage shooters than speed.
Good luck to you both!