Maybe a little teddy with something they like with it. Like a small yankee candle attached to the bear for your mum, chef bear with some kitchen item you think she would want/“need” and something you made and a scratch card or something if someone older buys it for you for grandma.
Idk, this might be cute or bad. I forgot mothers day (it is a different date in the UK) so I might not be the best person to ask. 