diff --git a/unpacked/jax/element/mml/jax.js b/unpacked/jax/element/mml/jax.js
index f401a5c61..40f54620f 100644
--- a/unpacked/jax/element/mml/jax.js
+++ b/unpacked/jax/element/mml/jax.js
@@ -397,10 +397,12 @@ MathJax.ElementJax.mml.Augment({
     },
     setBaseTeXclasses: function (prev) {
       this.getPrevClass(prev); this.texClass = null;
-      if (this.isEmbellished() || this.data[0].isa(MML.mi)) {
-        prev = this.data[0].setTeXclass(prev);
-        this.updateTeXclass(this.Core());
-      } else {if (this.data[0]) {this.data[0].setTeXclass()}; prev = this}
+      if (this.data[0]) {
+        if (this.isEmbellished() || this.data[0].isa(MML.mi)) {
+          prev = this.data[0].setTeXclass(prev);
+          this.updateTeXclass(this.Core());
+        } else {this.data[0].setTeXclass(); prev = this}
+      } else {prev = this}
       for (var i = 1, m = this.data.length; i < m; i++)
         {if (this.data[i]) {this.data[i].setTeXclass()}}
       return prev;
diff --git a/unpacked/jax/output/HTML-CSS/jax.js b/unpacked/jax/output/HTML-CSS/jax.js
index ceccb2a84..4f4449df4 100644
--- a/unpacked/jax/output/HTML-CSS/jax.js
+++ b/unpacked/jax/output/HTML-CSS/jax.js
@@ -1674,9 +1674,8 @@
 	  else {box.bbox = this.HTMLzeroBBox()}
       },
       HTMLboxChild: function (n,box) {
-	if (this.data[n]) {return this.data[n].toHTML(box)}
-        if (!box.bbox) {box.bbox = this.HTMLzeroBBox()}
-        return null;
+        if (!this.data[n]) {this.SetData(n,MML.mrow())}
+	return this.data[n].toHTML(box);
       },
 
       HTMLcreateSpan: function (span) {