My DH wants to start using a Littlelife backpack carrier for walks and days out with our baby aged 11 months. Just wondering is it safe for a baby to nap in these and where does their head go? Our baby currently only likes the forward facing position of our baby carrier which isn't comfortable for long and not good for naping so we always take the pram when we go out but would like to go more places that are not suitable for the pram.