Two expressions contributed by my son and daughter have become part of the family dialect:

My son, on being told that we couldn't buy him a certain toy for lack of money (white lying), responded: "But we can buy money from the bank, Daddy".

My daughter, just as she was learning to speak, one day drove my wife spare while she was out shopping, demanding "two mummies". Both were getting so frustrated and close to tears when they returned, that I offered my daughter some strawberries, which I knew she liked, just to quieten her down. At which, she smiled happily, showed the strawberries and said "two mummies!". We still call strawberries that 18 years on.