The best card message is personal. Here are ideas to use or adapt.
'Thank you for everything you do and for being you. Happy Mother's Day — with all my love.'
'The world would be a less kind place without you in it. Happy Mother's Day, Mum.'
'From the person who made all your grey hairs. Happy Mother's Day — worth it though?'
'Thank you for always being there and for everything you do. Happy Father's Day.'
'The best taxi driver, bank and advice service I have ever had. Happy Father's Day, Dad.'
Make a free Mother's Day card or Father's Day card and personalise the wording.