Non-negative idiom for someone arriving the moment you were talking about them?

Your ears must be burning.

Said of someone who appears during or just after one has been talking about them.
_{Wow, your ears must be burning because Mom and I were just talking about you and your new job.}

_{Source: The Free Dictionary}

This is considered neutral to positive, as it would not be said in some sort of admission of guilt about talking behind someone’s back.

While searching I came across

Talk of an angel and you'll hear his wings.

quoteslyfe.com See also WR Forums

I have never heard it, but evidently it's known in English.

The "bird" part of the metaphor appears in the second half of the proverb: "Speak of the Devil and he always appears; speak of the Angels and you can hear the flutter of their wings." Robert Palmatier; Speaking of Animals: A Dictionary of Animal Metaphors (1995)

“Talk of an angel and you will hear his wings." Evelyn Blücher; An English Wife in Berlin (1920)

Ah, talk of an angel and you will hear his wings. There he is. Done anything, Armitage? A. W. Medley; My English Diary (1908)

Speak of angels," said the manager, cheerfully, “and you will hear the fluttering of their wings." William Nicolls; Wild Mustard (1914)

There is an English proverb that says: “Talk of angels, and you will hear the flutter of their wings." There is another which runs: "Talk of the devil and you will see his tail." Prentiss Ingraham; Buffalo Bill Among the Soux (2021)