With the increase of computational thinking (CT) tools in education, there are questions as to whether and how CT might support and/or hinder algebraic thinking of young children. Utilizing seeds of algebraic thinking, we add to this scholarly discussion by presenting examples from a CT activity with four-year old children in which we illustrate how young children are engaged in early algebraic thinking. More specifically, we highlight children's pre-instructional engagement with replacement, a precursor to the concept of variable. The included examples add to our limited scholarship regarding young children's (i.e., ages 3 to 5 years) early development of algebraic thinking of replacement through an unplugged activity that can be implemented within multiple learning environments within children's larger STEM ecosystem.