have been running since march (have dsses aged 4 and 2 - prior to march had done half-hearted running)
am running on average 3x a week. total maybe 25-28k
longest run so far 13k
have done one 10k race (49:42) and signed up for a couple more
am starting to think about signing up to a half-marathon but am hesitant. local one is in october, so a good time wrt a bit more training, but it' quite hilly
so - would it be quite an easy move to go from where i am now (a couple of 10ks a week plus an occasional slightly-longer one) to 21k?