My son has just turned 3 and while he enjoys walking most of the time I am still finding lots of opportunities to babywear (or preschoolwear to be accurate!). I find myself wearing him quite often still although generally not for long periods of time. My son is usually happy to play nearby at home. He is still napping most days but is beginning to give up his nap so sometimes he skips one and will get quite cranky by the evening and want to be with me. I am not always able to hold him on my lap if I need to make tea or get school things ready for the next day so putting him and a carrier will allow me to get on with things I need to do. When he wakes in the morning (and when he does nap) he doesn't wake up gracefully and needs to be held for a while so babywearing is useful for that too.
I try to time outings before lunch (or after a nap) but it's not always possible. I bring a carrier with me so if he gets tired and I can carry him on my back (and finish my shopping in peace!) Sometimes his legs just get tired or he just doesn't feel like walking that day and it's often easier just to carry him rather than persuade him to walk when he doesn't want to (which always results in taking half an hour to walk half a block! I will sometimes carry him too when he is walking very slowly but I need to be somewhere on time (ie the school run) although I find I rarely need to do this now as he usually enjoys the walk and likes to keep up with his sisters but it's nice to have a full buckle in my bag just in case.
Recent other reasons I have worn my preschooler in the last month or so.
We went for a walk and his thongs kept falling off (note to self -don't by thongs for 3 year olds!)
I was visiting my Mum and he was tired so I took him for a walk around the block instead of trying to get him to sleep in a strange bed (then I could just easily transfer him to a spare bed once asleep).
Was late getting ready to go to grocery shopping. It was around naptime but I really did need to get my shopping done so ended up carrying my sleeping son around the supermarket.
I took him for a walk to the park and his legs got tired!
Just because! (cuddles with a preschooler are cozy!)
I have a handy bag which is roomy and comfortable to wear and I still keep my carrier in it whenever I go out with my toddler. I am noticing I am using it less than I once did but I still use it often enough that I am motivated to bring it with me. I usually bring a full buckle. Its convenient for ups and downs, not too bulky, and is two shouldered which distributes my sons heavy weight well. I used to bring a ring sling for short trips but recently my son has been feeling heavy in a one shoulder carrier probably a combination of his weight and me using the sling less so my muscles are not used to it anymore. I still love my ring slings though and use them at home if my son wants to be held and I just want to finish what I was doing before sitting down with him. I still like using mei tai's and half buckles at home but otherwise mostly use those if I am out for the whole day, just because they are a little bulkier to carry just for a short trip. They are great for bigger kids. By tying the shoulder straps in different ways or by wearing the waist apron or non apron and varying where I tie/buckle it, I can customize where I want my son's weight distributed.
All photos on this page show toddler sized carriers. I can carry him in standard sizes still (he's around 50th percentile for height) but toddler fits him very nicely now and is a better height for arms in.
I love to sew. I have five curious and active kids who keep me busy!