CSNK2A1 and Becker muscular dystrophy: An SNP microarray revealed an interstitial duplication in exon 55 of DMD suggestive of Becker Muscular Dystrophy (BMD), but his degree of delays led to follow‐up exome sequencing revealing a pathogenic CSNK2A1 variant diagnostic for Okur–Chung Neurodevelopmental Syndrome.