A load of muslins, some brownies and ready-made (but excellent pies). A toy if you must. Maybe a nice candle and a card saying "congratulations - it gets better I'm told"?

Genuinely haven't heard of a suitcase being measure in pounds before. Kg for luggage (or people), stones (for people)... pounds are for like... I dunno, flour? Sugar in an old-timey cake recipe? Surely your French heritage is simply screaming at this point?