I'm so happy to report that after three attempts by me, two attempts by Gary, one by Marianne, it was Lesley who managed to seal the deal this morning.
Thursday evening I managed to trap one more kitten, but the last one, a fluffy little calico, eluded me. I tried again last night to no avail. With the THS appointment looming today I asked Lesley to try this morning. She tried a new tactic, she trapped the mom and used her to lure the last kitten.
I was elated when she called me just minutes ago to say she got them! Now the family will be reunited and go to the THS to find homes! Just in the nick of time as construction is starting on Monday. Woo hoo!