A. There's a lot you can do to help keep Daddy fresh in her mind. But the big picture to keep in your own mind is that over the long haul of her life, these 15 months will represent a mere blip. Even if she does forget him (because toddlers are the Zen masters of living in the moment), she has the rest of her life to get to know him again.
Ironically, his absence may be much harder for you -- odds are you'll miss him several times a day and in an aching way at night. Stay in touch with good friends and family, who can ease the loneliness.
While he's away, to help your toddler remember her father's face, keep a photo of him (preferably one with her in it too, for context) in her room. She can kiss him good morning and good night. Of course, your husband can write letters that you can read to her, but don't expect her to listen intently and tear up like you do. She's got bigger things to worry about this year (walking, talking, redecorating...with crayons) than how her dad is doing.
Before he leaves, your husband may want to make a tape recording of bedtime stories for your daughter. Hearing her father's voice as she drifts off to sleep, along with having family videos for occasional daytime viewing, will make Daddy seem real. And if your husband wears aftershave or cologne, give your child a whiff of it every so often, to jog her olfactory memories, or put one of his old T-shirts in her crib for her to cuddle with. It may make her feel both happy and sad, but then that's what loving someone far away is all about.
Trisha Thompson is a contributing editor to Parenting and a former editor-in-chief of BabyTalk.