Sound symbolism—the association between word sounds and meaning—has been shown to be an effective communication tool that promotes language comprehension and word learning. Much of the literature is constrained to investigating sound as it relates to physical characteristics (e.g. size or shape), and research has predominantly studied the phenomenon in adults. The current study examined the sound symbolic wham-womb effect, which postulates that words with the /æ/ phoneme are associated with increased arousal while words with the /u/ phoneme are associated with little to no arousal. The effect was tested in both adults and children aged 5-7 years old using a word-to-scene matching task. Participants were presented with two pseudowords (differing only by their vowel phoneme: /æ/ or /u/; e.g. smad and smood) and two scenes depicting an animal in either a more arousing or less arousing situation. Participants were then asked to match which of the scenes fit one of the pseudowords. Results showed that the trial-by-trial performance for adults and children were significantly greater than chance, indicating that the wham-womb effect is exhibited in both adults and children. There was also a significant difference in performance between adults and children, with adults showing a more robust effect. This study provides the first empirical evidence that both children and adults link phonemes to arousal and that this effect may change across development.