Be honest. Tell your little ones about the baby, and gently paint the picture about what might change. Let them know that baby is permanent, that sometimes mummy and daddy will be tired or busy, and that mummy will have to go away for a while. Give them time to digest these facts, to ask questions and to grieve a little.
Acknowledge the changes in role. Stop referring to your toddler as “baby,” and call him the “big boy,” the “big brother” or “mummy's helper.” This will give him a sense of change, of seniority, of responsibility and of purpose. Acknowledge his special position in the family, and talk about “our baby” or “your little sister.”
Cultivate affection early. Allow your toddler to kiss and cuddle your tummy, to chat to it, read stories, and show it his teddies. Let him feel baby kicking, and tell him that baby is excited to play with him. If you can, take your toddler to your scans and antenatal appointments, so he can see and hear baby, and get excited about meeting her.
Empower your toddler. Allow him to make choices for baby and for himself. Let him choose baby's clothes, nursery colours or perhaps even a name. Consider letting him chose a 'big boy' bed, or whether he wants to use the potty or the toilet sometimes.
Whilst it’s difficult to truly prepare a toddler for something they really can’t understand completely, a few little steps will go a long way to having an excited (and hopefully sometimes helpful) older sibling.