расти большой, не будь лапшой

Literally, “grow bigger, but do not be a noodle”; chosen for the rhyme and cadence.

• IPA^(key): [rɐˈsʲtʲi bɐlʲˈʂoj | nʲɪ‿ˈbutʲ ɫɐpˈʂoj]

расти́ большо́й, не бу́дь лапшо́й • (rastí bolʹšój, ne búdʹ lapšój)

1. (idiomatic, colloquial) may you grow bigger, but not weaker (parting words or a well-wish from an adult to a child)
2. (idiomatic, colloquial) bless you, gesundheit (said to someone who has just sneezed)

   Synonym: будь здоро́в (budʹ zdoróv)

When used from an adult to a child, it suggests the child that they should also grow in character and maturity, not only in physical strength or age.