Roaming in the Gloaming

Yesterday evening, at sunset, very dim. Delighted to see Half-tail scrabbling and gnawing next door. Not glad about the mange, of course, just the fox!
Things have been eerily quiet lately. In previous years we learned to expect a very low profile at this time of year, it's cubbing time.
I cautiously opened bedroom window and did not spook it off. Poor fox, so itchy! I have been dosing mange medicine in the nightly food but it hasn't begun to work. Reason for anxiety is, the dens become infested with mange mites and the cubs catch it and eventually pass it on.
In the deep dusk, a fox is expertly camouflaged on dried-out brownish grass. Half-tail scrabbled about and came and went a little and then mooched away down the near path towards the old den area, in the corner backing on to our garden shed!
I continued to watch with my trusty binocs in hand, because i could hear rustlings in the bushes, and scuffling, and alarm calls from blackbirds.
When foxes first became numerous around here, about 10 years ago, magpies would alarm loudly, but they don't anymore. Some birds still do, but it's more usually a cat that sets them off. I was hoping that it was not a case of tiny new cubs and prowling cat, a dangerous mixture.
Glad that Half-tail had seemed to be going home, I was surprised by what happened next. A second fox appeared on MY side of the wall, moving rapidly up the garden towards me. A babysitter going off duty, or an intruder seen off? hard to say, because in the almost-dark I couldn't ID reliably, except for a smooth round tail with rounded white tag. Seemed a bit smaller than I remember Bigboy, though hard to say at teat angle.
Straight up the garden, small detour to feeding-dish(empty) and to the terrace pond. I watched from above, barely fifteen feet away! Fox paused as if to drink then wriggled iunder the rose-bush to the other side of pond, just where the frogspawn is!
Then quickly down the garden again, clearing minor obstacles with a beautiful easy leap.
Vanished, then reappeared in Martins. Quick check in front of their kitchen window - she feeds them too- then swiftly out the front along the well-known foxes' passage, and out of sight.
All this is absolutely classic fox behaviour! My guess is that there are cubs, that they are in the old den area, very secluded. That Half-tail is the mother snatching a few rare moments off duty and the other one - Bigboy?- is the male who keeps a watchful eye nearby, and forages for the vixen and himself. The businesslike patrol of borders and feeding-sites was spot-on. And so is the recent radio-silence in the garden.
If the second fox tonight was not Bigboy, it could be a related female, often found in fox groups doing just what this one was -babysitting and foraging.
Now we need to keep a close but very discreet look, and supply plenty of mange medicine.

Later on Sunday morning: In the interests of completeness, I checked the pond. Well, what do you think? Was the precious spawn gone? No, indeed! In fact, there is a new clump floating in the middle!
So, foxy was looking not for spawn but for frogs! Grrr!