Hurray! I am quite chuffed that we published our paper entitled “Revisiting the relationship between birth order and romantic jealousy: No support for an effect in four samples.” This is the work of multiple students who worked with me to collect multiple samples on birth order and jealousy. To summarise in a one-liner: across four samples we find no evidence that birth order is related to romantic jealousy. Read all about it here: https://doi.org/10.1016/j.paid.2026.113638