You're right, ensure was the wrong word, in fact I was quite keen to dissuade him from following in my footsteps (at the time I could see design and manufacture in a lot of the areas I had worked in leaving the country). Luckily he's turned out very flexible, with a decent S/W and H/W balance [Edit: , a healthy CV] and a has a decent, secure, and interesting, niche with a large employer.
The other chose Geology fairly early, so the subject never really came up - I'm not sure Sheldon would have been so relaxed about that one though.