Hi Captain the answer to 10a 24a is "Family member" and this reference 10 24 is included in a number of clues - so you automatically would think father, mother son etc - and someone cold or even doing the crossword would be totally flummoxed, until you get letters in. One particular answer could only be one word, and then you think "how on earth is that a family member. Then it hits you and you have a theme and then the other themed answers become a doddle. But to start with, you don't know there is a theme!
Best wishes!