After a couple weeks of fighting with our nearly five year old son (I shall call him Aki which is the Greek affection for "little man") over the merits of wearing underwear, I took him to the store and had him pick out some ones he wanted. Instead of the ones with Lego on them that he had at home, he wanted ones with "little legs". Ah. Alright then. I had major sticker shock over them as the boxers and trunks were roughly $6 a pair, whereas the briefs were less than $2 a pair. So we went to Fabricland to buy some waistband elastic instead.
I had about 4 metres of a green interlock at home that I had picked up for $3 last summer at an Our Social Fabric sale (textile recycling sale of amazingness), already had green thread and some wooly nylon for the bobbin with the double needle, so I was all set.
I thought these trunks were really clever. The only seam, other than the inseam, is at the front with the pouch, so they are super quick and easy to put together. I used my serger for the seams and a double ballpoint needle with wooly nylon bobbin thread for the topstitching. A quick blast with the iron to coax the threads into relaxation, and they were ready to wear.
At least with so many sizes in one pattern, if I'm stuck sewing him underwear for many years I'll never have to buy another pattern.