not sleeping in cot during the day

Hi
For the past 2 months my 4 month old has been sleeping with mum in a hug a bub (sling) during her day sleeps. We started doing this when she refused to sleep more than 20 min at a time during the day and it was affecting her feeds and she was not putting on much weight. The sling is doing a great job and she is thriving but I'm worried about the future when she becomes too heavy or the weather too hot. Has anyone else carried their bubs around all day? Also, has anyone got any ideas for changing this routine when the time comes?
Claire and Georgia

I would like to say first that alot of people do the attachment parenting (carrying bub around all day) and it works for them.

As for not sleeping in the cot during the day, we had the same problem, so during the day my son sleeps in my bed (by himself) and at night he sleeps in his cot. He also has a soft rattle he gets given when in my bed during the day and at night he is given a different soft rattle. This has been happening for a few months now and he can now distinguish that when he gets a certain rattle it means sleep etc.

Let us know if that works for you.