I know the equivalent Dutch pronoun is 'elkaar'. Do other Germanic languages have a similar word? English? No. *Hulle kyk vir mekaar.* 'They watch each other.' *Drie jaar na mekaar.* 'Three consecutive years *lit.* Three years, one after the other.' Other languages have something similar?
Dutch officially recognizes “elkaar” which has the same meaning. “mekaar” is also region ally used in the Netherlands as a dialect/slang term with the same meaning. I’m suspecting this is the origin of the Afrikaans word but I’m not sure.
https://www.vandale.nl/gratis-woordenboek/nederlands/betekenis/ELKAAR#.YdMU1Ld1Y0E