Need help with linear mixed modeling in SPSS

So I've looked a quite a few tutorials and forums to see if anyone has posted something similar to the dataset I'm analyzing, and it doesn't seem like anyone has. I more need someone to tell me if what I'm doing is right or not.

My data is looking at maternal cytokine levels during the gestation of two of her kids - one that has been diagnosed with autism, the other is neurotypical.

I originally ran paired ttesting to look for significant differences, but the PIs for the study want me to run linear regression on the data, taking into account each mom's data by adjusting the intercept.

First question: Am I interpreting what they want me to do correctly as running a linear mixed model for each individual cytokine, specifying the intercept for each mother as a random effect?

Assuming that's correct, here's my second question: How do I set up this data in SPSS?

Here's what I have so far:
-I have the data set up so that one variable is listed as the mother's ID, another variable identifying the case status of the child (1=ASD, 2=TD), and then a variable for each cytokine. In other words, each mother has 2 rows of information, one for each pregnancy.
-I go to analyze, mixed model, linear. I put the mom's ID variable under the subjects box, and the case status variable under the repeated box, and I'm specifying the covariance type as unstructured.
-I choose the cytokine of interest as the dependent variable, and identify the case status variable as a factor
-Under fixed, I add "case status" to the model box, leaving "include intercept" checked
-Under random, I add "Mom ID" to the combinations box and click the "include intercept" and leave covariance type as unstructured (although it always seems to change it to identity)
-I choose parameter estimates, covariates of random effects, and covariants of residuals under statistics.

Does this all look right in order to assess the relationship between case status and gestational maternal cytokines while identifying the intercepts as a random effect?

Thanks for any and all help!