Introducing a kitten to a resident cat?

We had two 16 month old sisters Poppy and Daisy up until last week when we were devastated to find Daisy had been killed by a dog. Being in shock and very emotional we thought should we get another so Poppy isn't alone in the cattery when we go on holiday. So we have gone and got another female 8 week old kitten. Having read previous posts on here now after the event i can see i should have put the little one in a separate room but i was unaware of this and brought her straight into the house. I knew Poppy wasn't going to take to her straight away and it has only been a couple of days anyway. Poppy has spent a lot of time outside just coming in for food and we are giving her a lot of attention when she does come in and when we see her outside as well. We have been putting the little one at night in her own room in the middle of the evening so Poppy eventually comes in and sits with us for attention. However of course when they do meet Poppy is spitting a bit she did lick the little one this morning, and then the kitten moved quicky like they do and got a soft bashing on the head. Poppy will accept this kitten wont she? I am very worried about this. They are due to go to the cattery together in four weeks as we have holiday booked and will be in the same enclosure then. Also to add insult to injury we are due to get a puppy er spaniel in 6 weeks after the holiday which was all organised before the dreadful happening of last week to Daisy.