Boris Lapin's birth name is Lapin, Boris Matveyevich.
Ron Lapin died in 1995.
boris I do not believe Caillou's last name is Boris because Boris is his dad's name. Therefore, while not unheard of, his dad's name would be Boris Boris and his mom's married name would be Doris Boris. I am thinking this is not the case. I do not believe Caillou's last name has ever been mentioned (at least not on the tv series).
Boris Carloff
Nino Bellini's birth name is Giovanni Bellin.
Shyne's birth name is Jamal Barrow.
Nicole Lapin's birth name is Nicole Miriam Lapin.
Boris Lapin was born on July 16, 1905, in Moscow, Russian Empire [now Russia].
Boris Sarbek's birth name is Boris Saberkoff.
Boris Novak's birth name is Boris Novak.
Boris Tumarin's birth name is Boris Tumarinson.
Boris Kabur's birth name is Boris Bargunov.
Boris Kashev's birth name is Boris Kashev.
Boris Lapin died in September 1941, in Kiev, Ukrainian SSR, USSR [now Ukraine] of WWII casualty.
Boris Altshuler's birth name is Altschuler, Boris Abramovich.
Boris Aplon's birth name is Boris S. Aplon.
Boris Arakelov's birth name is Arakelov, Boris Arshakovich.
Boris Ardov's birth name is Boris Viktorovich Ardov.