i want to get a bike, but more so, i want to get a bike at the same time as my mom. shes a small gal, about 4'9 - 4'11 (i cant remember

i was thinking of supprising her by taking her up to anchorage for a weekend msf rider course next spring, and then we could get our bikes together around the same time. i can pay for mine, and i think she has the right funds for a bike her size.
the problem is, should i supprise her with the course, and plan it with her friends? or should we schedule this? every time i try to supprise her, it seems to turn out well, but this is not some little thing. this is userping her time and popping her into something she may not be ready for. i dont know, any suggestions?