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Discoveries by the NASA TESS mission of nearby stars hosting planets either side of the ..radius-period valleyd_comma are presenting the very first opportunities to study the feature in the context of individual systems. Knowledge of the shared high- energy irradiation history of planets in such systems is a powerful tool that could provide crucial evidence towards determining which of the proposed mechanisms for sculpting the valley is correct. We propose XMM-Newton observations for two nearby TESS systems with planets either side of the valley comma with the aim of measuring the XUV environment in which they reside. From these data comma we will be able to investigate the photoevaporation and evolution history of the planets comma and place them in the context of the wider population and the generation mechan