You asked

How can my two older children help with the new baby?

How your children react to a new baby will depend on them. While you may want to get them involved in caring for the new baby, they are probably more concerned with maintaining their special relationships with you. How they react to helping, and what they can help with, will also depend on their ages.
An older child of five or six can be a genuine help with a lot of baby related tasks. He or she can help you bath the baby, push the stroller, fetch nappies and other items and help to powder your baby. A younger child, on the other hand, of around one and a half to two years, will be less able, and less inclined, to help out. Try to include children of this age in other ways. Allow him or her to sit on your lap while you read stories or sing songs, for example.
If you’re finding it difficult to share your time and attention between three children at the same time then getting your partner involved can also help. Have him play games with your older children while you’re with the baby, or alternate, allowing him to bath or change your baby while you play with your children and then swapping the next time.
The most important thing is to make sure that your older children don’t feel left out, and that you reassure them that they are still special and loved.

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