Legzz, let DD and DH2B help. You might have to spell it out for them until they get the hang of it but I'd start letting them become involved in helping you. If you're trying to do it all yourself and not accepting help from anyone they'll never have the chance to pitch in. And this can make them feel better about themselves, too. Most kids love to feel like they're making a positive difference. They just don't always know what will help us the most. So we have to take the lead and show them....then let them take the initiative and help. DH2B might be a different story. He really should know by now what you need help with and what will make your life easier.
Happy Birthday to DD!