"Ariana was delicate!" said Doge desperately. "Her health was always too poor to permit her -"
"To permit her to leave the house?" cackled Muriel. "And yet she was never taken to St Mungo's and no healer was ever summoned to see her!"
"Really, Muriel, how you can possibly know whether -"
"For your information, Elphias, my cousin Lancelot was a healer at St Mungo's at the time, and he told my family in strictest confidence that Ariana had never been seen there. All most suspicious, Lancelot thought!"
Harry Potter and the Deathly Hallows
I have a hard time to understand "All most suspicious" in this context. "All most" doesn't look a correct phrasing. How should we understand it?