In order to illustrate a Cauchy problem for first order ode with infinite family of solutions, I would plot the parametrized solution and having the possility of control the value the parameter through a slider.
To be complete the Cauchy problem is y'=sqrt(|y|), y(0)=0, and the parametric solution is y_c(x):={0, if c=>x; (x-c)^2/4, if x=>c}.
So I would get a plotting of y=y_c(x) with a slider to control the value of c.
Thank you.