There is no biblical reason to believe that these siblings are anything other than the actual children of Joseph and Mary. Those who oppose the idea that Jesus had half-brothers and half-sisters do so, not from a reading of Scripture, but from a preconceived concept of the perpetual virginity of Mary, which is itself clearly unbiblical: “But he (Joseph) had no union with her (Mary) until she gave birth to a son.
Walang dahilan sa Bibliya upang paniwalaan na may ibang kapatid si Hesus maliban sa iba pang mga anak ni Jose at Maria. Hindi ang Bibliya ang ginagawang basehan ng paniniwala ng mga sumasalungat sa katotohanan na may mga kapatid na babae at lalaki si Hesus bilang Tao kundi ang teorya na nanatiling Birhen si Maria hanggang kamatayan na isa ring katuruan na hindi ayon sa Bibliya.