I'm no Columbo but...
"...white and grey gym leggings..."
"...her normal daily walk..."
Call me old-fashioned, but I'm guessing either her dad's dead or he's a f***** b****** if he's okay with his daughter going out for a "walk" in a part of the country that is notorious for being a hotbed of Bangla and Pakistani activity, innocuous or otherwise.
My cousin who is in his mid 40s was telling me that back when he was younger Sikh parents really frowned upon their kids having love marriages even if it was with some from the same religion and caste love marriages were still frowned upon, and most parents wouldn't allow love marriages, but look at it now! parents themselves are telling their kids to find someone themselves. Love marriages have become the norm. God knows what the teenagers are getting up to! During english katha at the gurdwara one of the Singhs said every 10 years there is a big cultural change in our community, i now can see what he meant!